An atom's first 2 energy levels are filled and there are 2 electrons in the third energy level. It's atomic number is:

If 1.63 times 10 negative 4 of helium dissolves in 100.0g of water, what is the concentration in parts per million

One of the few xenon compounds that form is cesium xenon heptafluoride (csxef7). how many moles of csxef7 can be produced from the reaction of 13.0 mol cesium fluoride with 12.5 mol xenon hexafluoride? csf(s) + xef6(s) csxef7(s)

List the path of the respiratory system